Reciprocating abrader



Feb. 9 1926.

1,571,953 c; D. KNowLroN RECIPROCATING ABRADER Filed Feb. 12, 1920 Y .51@MQW Patented Feb. 9, 1926.

UNITED s'ra'lx-:s

y vr1,571,953! PATENT oFFicE,

CUTLER D. KNOWLTON, BEVERLY, MASSACHUSETTS, .ASSIGNOR TO UNITED SHOEMACHINERY CORPORATIQN, QF PATERSON, JERSEY, A CORPORATION OF NEW JERSEY.

encrrnocarrnc Baarn-n.

Application filed February L2J 1920. Serial No. 358,054.

To ail whom t may concern v Be it known that I, CUTLER D. KNowL'roN, acitizen of the United States, residing at Beverly, in the county ofEssex and State of h/lassachusetts, hav-e invented certain Im--y'pro'vements in Reciprocating Abraders, of which the followingdescription, in connection with the accompanyingdrawings, is aspecification, like reference characters on the drawings indicating likeparts in the several figures. n

This invention relates to machines for grinding edge tools. Theinvention is herein exemplified with particular reference to thegrinding or sharpening of the cutting edges of dies such as are employedfor cutting out blanks from sheet material. Dies of this character, inplan outline, describe closed figures and usually have abrupt re-entrantangles or corners. They are employed in cutting out shoe soles anduppers, the inetlio ofl'use involving the placing of a die upon a sheetof stock while the latter is supported upon a cutting block, and thenforcing the die toward the block to cut out the blank. Obviously if thecutting edge of the die is not uniform 'some portions thereof will beforced farther into the block than other Y portions, resulting in undulymarring ther surface of the block and sometimes causing ter referred to,which are commonly known 'y as clicking dies, it is customary to abradeboth the inner and outer surfaces of the strip ofpsteel to remove thedecarbonized skin. and to produce or sharpen the cutting edge of the dieby grinding the out-er or inner face ofsaid edge to a bevel. Owing tothe angular form of these dies in plan outF line, it is difficult toproperly grind the corner portions especially when the bevel .is 'aroundlthe inner face of the cutting edge.

To act upon the ire-entrant angular portions it is customary to employ afile because a wheel, owing to its necessary shaft and drivingconnections, can not be made to operate in the re-entrant angles unlessthe wheel be made very small in 4which case the peripheral speed isinsufficient to be effective and the bevel produced would be excessivelyconcave. Furthermore, for the best work, a die of the @hamster referredt0 Should have thebevelled faceof its cutting edge as nearly brate oroscillate the file laterally during each stroke so the teeth willoperate in one directionY and clear the work on the return stroke toavoid distortion of the shape of the cutting' teeth. Moreover a file, ifused continuously for a material lengt-h of time,

is liable to overheat the work and become overheated itself andso affectthe temper of the die and have its own teeth softened. rfhis liabilityof overheating exists even whenl filing slowly because of the `increasedfriction due to the necessity of bearing harder on the work to get anyaction at all. To re-state the objection to the use 0f a file it may besaid, therefore, that whether operated at high or low speed a file isliable to overheat the work and. become overheated. On the other handagranular abrader Composed of such material as corundum, carborundum Yoremery does the best work at high speed with light pressure against metal`because the velocity of the abrading particlesy aids in carrying theminto and through metal without overheating it or being itself affectedby heat.

It is to overcome the above explained and other difficulties attendantupon the use of a grinding wheel or a file, or the use of both on a die,that important features of this in vention have been developed, anobject being vto provide a machine capable of uniformly grinding orsharpening either the inner or outer bevelled faces ofcutters such asclicking dies, having especial reference to reentrant angular portionsof said dies.

With this object in view, a feature of the invention consists inproviding a non-rotary grinding member which is angular in crosssectionand is mounted toV reciprocate kin aj straight line, andf means hereinillustrated as a. high-speed pneumatic motor having direct connectionwith the grinding mem bei" whereby it is adapted to reciprocate thelatterwithout shock at a linearvelocity substantially approximating theperipheralV speed of an yeffective rotary grinder. thus lreciprocatingthe grinding member at high speed, a maximum of cutting efficiency willbe obtained and tendency of partlcles By les ot eniery or other abrasivesubstance to brenl; ottl troni the grinding member is reduced to itininiinuni. As a result, friction between the grindinnienlber :ind thework is reduced :1nd overheating ot the grindingl member is avoided.

The invention further elnirueterized by the combination. with n grinderol the clnss described, ot nn inclined n'orli support surroundingl thegrinder :ind capable ot being` rotatably adjusted to carry differentportions ot' the Work into Contact with the grinder without changing theinclinntion of the n'orh relatively to the grinder. As slionn. the worksupport is in the forni of :i centrally apertured, disk-like trible sindis supported by arnis of dili'erent lengths rieing1 troni o ring whichis mounted to turn ilreely Within :1 stationery circular guide.

Dies of theY type known :le clicking dies :1re eo formed tlnit theubrupt angular parte tliereoi" constitute but snnill portioi'is oyt theentire cutting edge. A granular nbrader haring' u sli-erp ingle or edgeto operate in re-entrent angles of the die would be shortlived if itsSharp edge were to be used when not necessary suoli us on portions ofthe die not abruptly re-entrunt. Therefore :mother important lfenture ofthe invention ooniprieee, n grinding` ineniber angular in cross`ejection :ind h. 'ng its angles oli vury- .ing dejrrees oii sharpness.ln the use of such nienibeig. u portion having the slnirper :ingle willonly be used when operatingon n reentrnnt :ingle of the die.

Further tentures oil the invention ineludinn' eer-tuin detnils otconstruction :ind Conibinutions of parte will non' be denorilied withreterencel to the :iccoiinninying4 drawings und pointed out in theclaims.

ln the drawings,

Fin'. l is n perspective View of n niecilniniiun einbedyiire` myinvention;

Vin'. is n side ele ration partly broken out or in section; und

Fig. 23 represente n.. section through the 1grinder on line 5 3 ot Fig.i?.

lflieillnstrirted preterred torni of the in.A rention comprises nl baseor Standard havinir suitably secured to its upper end :i plu- 'elity otbracketirrins 113 the upper endg.; ot which support zr circular guide inthe torni ot ir fixed ring lit. 'Ehering letnnd:the erin .t3 muy eoneistot n single meting.

:in upper ring is mounted upon and enitebly secured to the, upper tace4of the ring` til es, by serews 1G, sin annular reeese being; torinedbetween the rings li` und lili to receive the ldnlgeL 1,8, of n.rotntiyely ndiuetnble ring' lli, seid ringr 1T farrying nu nrnr it) undun upright 2Q, the lutter extend inn` to n height greater than the erinil).

The Work support or table 2l ha fing :i ceutrnly hole 22 is proyidedwith eers Q3 pivotully connected by n` pin 24 with the upper end ot:ii-ni 19. Dininetrioelly oppoA sito the location ol. the pirotnlSupport 2l :1re eers Q5 depending 'troni the trible, enid -cnrsreceiving between tliein the upper end olE the upright 2t), n screw orbolt, having n wing nut E26. being employed to secure the eersrelutively to the uprightl 2o. 'llo perinit olI soin-o :uljnstnient otthe inelinntion ot the norlt trible 2l. euitnble prorieion is runde suchne by menne ot ii slot Q? torined in the upright O, the screw or boltharing the wing' nut persing through mid slot..

The buse or column 'lil eruniorts the motor lor netnnting the grrilnler.l.' do not lin'iil; niyselt to any purtieulnr niotor employed but torreasons hereinzilfter explained l". preter n pnruinnti f lmotor enpubleolf :in exceedn ingly hiih speed oiI roeiproention. ,ln the illuetrntedembodiment ot the invention, the cylinder o t :i pneuinntic motor ieindicated ut 28 :ind the pieton rod thereof :it Coupled to the upper endof the piston 25) is the core 30 of n grinder ol. preferablycoinprieing` n block ot eniery triunpgnlnr in cross :'ection. l do notliinit inyselt to this purtieulnr cross seetioinil sbnpe ot the grinder,but prefer it in order to ruin :iceeee more. readily to the re-entrnntportions oil? zi elinkiug; die. .is indicated in Figi'. 3, the threecorners: ot' the grinder :ire not alike. One :is :it 5R12 is quiteslnirp. another in; nt 33 is conlpnrntirely blunt, :1nd tlie third ne:it 3i-l; is intermediate :is to its degree oit bluntness. ln otherwol-ns. while the corner 33 is rounded to the curve oit n certniiiradius, tbe corner 3ftiis rounded to the curro ot n Shorter rudius. i

1lille-n the innchine is in operntioln the .motive fluid being` admittedtlirouiijll the conduit indicated :it do, the grinder reoimoentes :itvery hin-h speed in e straight. rea ticzil line. The upper end ot thegrinder if.; exposed so that when the inner trice oli the -uttin i ledile ol' the die ie to be grrtniud or elnirpe-ned, :mid die nn hedropped over the top ot the jrinner no tlnil :ill portions; ot it:lrlnnt eiiln'e rfiil be sneliporied by the table. @wing to the i'ncttlnit the tnbleiri mounted sotluit it een be rotiited. the operator cnnrotnte the tnble and ninnipulote the die ns to perform the printlingjoperntion pro LQjree iyely nlongg the inner -will ot the di# -andentireliiY :iround it. without altering; the tingle which the die`ground or sharp ened. Gt' coni be. some portions ot' tbe die" een beground by one ot tbe tint trices; ot the grinfiler. lVhen n very ncutere-entrnnt nngle is to be ground or .elnirlienedN the tnbliA und theWork nre rotntiul no that. tbe Sharp corner lf3 will uct in seidreentrnnt ungrlc. lVben :inii'ulnr portions; less acute, or when :ininward curve ot the die is to beinoved :ilonnin Contact.` with the.grinder, then the` trible n'ill be rotnted so tl :it the portion ofi"the die to be ground een be shifted intocontact with either of thecorners 33 or 34 according to the character' of the Work. 0f course, thevery sharp corner 32 will only be used when absolutely necessary in `order that the utility of the grinder as aperiodic use of the fiatadjacent sides otthe grinder. Y

I prefer to use a pneumatic tool for the reason that such a tool iscapable of operating without undue shock to parts of'its own mechanismat a speed so high that its linear velocity will substantiallyapproximate the effective speed of the periphery of a grind ing Wheel. Yf

Having' ydescribed my invention, What l claim as new and desire tosecure by Letters Patent of the United States is:

l. In a machine for grinding dies, an angular non-rotary grinder mountedto reciprocate in a straight path an adjustably inclined die supportsurrounding the grinder and being rotatably adjustable to bringdiil'erent parts of a die into contact with different portions of thegrinder, and a high speed pneumatic motor having direct connection withthe grinder whereby it is adapted to reciprocate thegrinder Withoutshock at a linear velocity substantially approXi. inating the effectivespeed of the periphery of a grinding wheel.

. 2. 5l machine of the character described, comprising a grinder, meansvfor reciprocating the grinder in a substantially verti# cal plane, aninclined work support sur rounding the grinder, and means for adjustingsaid supportv rotatively.

3. A machine of the characterv described,

Vcomprising a circular guide, a member mounted to rotate on the guide,an inclined work support secured to the inenlber, and an abrader mountedto reciprocate through an aperture in the work support.

4. A machine of the character described, comprising a circular guide, arotatable ring mounted to turn on the circular guide, an arm rising fromthe rotatable ring, an up right of greater height than the arm, anapertured work table supported on the arm and the upright in an inclinedposition, and an abrader mounted to reciprocate substantially verticallythrough the aperture;

5. In a machine of the character described, a grinding member havingflat sides for grinding the straight portions of a piece of work andhaving corner portions differing from one another in contour forengagement with different corners of the work, means for reciprocatingthey grinder,

v an inclined Work support surrounding the l grinder, and means forrotatively adnisting the inclined support to bringthe different parts ofthe Work into conta-ct with the de-V sired portions of the grinderwithout changing the bevel produced on the cuttingedge of the work.

G. In an abrading machine for operating upon the cutting edges of toolparts, au

abrading element, anl inclined rotatable work supporting tablesurrounding the abrading element, and means to vary and to control theangle of inclination of the table.

7. I n an abrading machine for operating upon cutting dies, an annularrotatable worksupporting table, an abrading element located centrallyof'the table and extending upwardly above the surface thereof, and meanstiltably to position the rotatable table at various angles with respecttothe abrading element.

In testimony whereof I'ha-ve signed my name to this specification. n

CUTLER D.V KNOVVLTON.

